Over recent years there has been a substantial increase in the number of thefts and burglaries. As a consequence, more and more businesses and individuals are purchasing safes with a combination lock for securely storing their valuables.
In order to provide the best possible security, these safes are constructed of strong, heavy gauge metal. They also include carefully machined tumblers to provide smooth and silent lock operation. Because of the craftsmanship and material costs involved in safe construction, a good safe represents a very significant capital investment.
One problem with combination lock safes is that they are only useful so long as the lock is functioning properly and/or the combination is known. If, for example, a malfunction develops in the lock mechanism or the combination is forgotten or the only person who knows the combination disappears or dies, the valuables within the safe cannot be removed until the safe can be opened in some manner. The safe could be opened by forced entry. Ideally, however, because of the significant investment a safe represents, the safe is opened by manipulation without damaging the valuables inside or even the safe lock so that the safe may be reused once the combination is again determined.
Conventional combination locks include a plurality of tumbler wheels mounted coaxially on a spindle and coupled in a unique fashion representing the combination. The spindle projects through to the outside of the safe door. A calibrated dial is attached to the end of this spindle. The coupling of tumbler wheels to the spindle includes lost motion connections that ensure the tumbler wheels may only be rotated and aligned when the dial is manipulated in the correct sequence and direction. The dial is mounted within a dial ring which typically has a reference mark scribed thereon. This mark provides a reference for the dial calibrations. In other words, the lock's combination is dialed relative to this reference mark.
A sliding bolt is contained within the safe door. This bolt is extended into the jam of the safe body to lock the safe. A fence lever is pivotally connected to the sliding bolt. In operation, when the tumbler wheels are positioned according to the combination, recessed gates in the wheels line up. The fence lever then engages these gates, allowing a nose of the fence lever to engage a spindle drive cam. Once this engagement occurs, the bolt can be withdrawn, allowing the safe door to be opened.
U.S. Pat. No. 4,662,201 issued to Peter J. Phillips, May 5, 1987, and assigned to the present assignee discloses a method for ascertaining the combination of a locked safe. This method includes drilling an inspection hole at a known position with respect to the dial through the safe door and into the underlying lock chamber. A specially tipped probe is then inserted into the lock and manipulated along with the tumbler wheels in such a fashion that the tumbler wheel gates can be found. From the position of these gates, the lock combination can be computed.
Similarly, U.S. Divisional patent application, Phillips, Ser. No. 004,155, now U.S. Pat. No. 4,714,386, issued Dec. 22, 1987 and assigned to the present assignee discloses an apparatus for carrying out the above method. Use of this apparatus requires removal of the safe dial and dial ring. A mounting fixture is then mounted to the safe door, in place of the dial ring. A derrick is then attached to this fixture to hold the drilling position and thereby facilitate drilling into the safe door. Use of this apparatus is limited to situations where both the dial and dial ring can be removed from the face of the safe door. In the event the dial or dial ring cannot be removed, this apparatus cannot be used. The removal of the ring is also time consuming and the separate fixture adds additional cost to the kit for carrying out the method.
A need therefore exists for an improved apparatus provided to hold a drill precisely in position for the drilling of an accurate inspection hole. The apparatus must be capable of mounting directly to a safe dial ring, negating the necessity for removal of same and eliminating the use of a separate mounting fixture. Use of such an apparatus, and related method would better assist locksmiths in opening most commercially available safes, including, of course, those in which the dial and/or dial ring cannot be removed.
Thus, this invention in its broader terms is directed to holding and supporting a locksmith tool on the door of a safe. More specifically, the tool's position may be precisely controlled so as, for example, to allow accurate locating, and then drilling of an inspection hole. The locksmith may then pass the fiberoptic element of a borescope through the inspection hole into the lock chamber. The borescope allows visual inspection of the lock tumblers including the gates, and thereby allows accurate determination of the safe combination.
The apparatus and method should also be useful to mount and firmly support an automatic dialer or other similar non-invasive device. Supported in this fashion, the dial may be automatically rotated back and forth until the combination is determined and the safe is opened.
Advantageously, the proposed use of this apparatus with either device allows the locksmith to open a safe without destroying the safe or its contents.